package com.cn.why.produce_pro.config;


import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.amqp.core.Binding;
import org.springframework.amqp.core.BindingBuilder;
import org.springframework.amqp.core.DirectExchange;
import org.springframework.amqp.core.Queue;
import org.springframework.amqp.rabbit.connection.CachingConnectionFactory;
import org.springframework.amqp.rabbit.connection.ConnectionFactory;
import org.springframework.amqp.rabbit.core.RabbitTemplate;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.beans.factory.config.ConfigurableBeanFactory;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Scope;

/**
 * Broker:它提供一种传输服务,它的角色就是维护一条从生产者到消费者的路线，保证数据能按照指定的方式进行传输,
 * Exchange：消息交换机,它指定消息按什么规则,路由到哪个队列。
 * Queue:消息的载体,每个消息都会被投到一个或多个队列。
 * Binding:绑定，它的作用就是把exchange和queue按照路由规则绑定起来.
 * Routing Key:路由关键字,exchange根据这个关键字进行消息投递。
 * vhost:虚拟主机,一个broker里可以有多个vhost，用作不同用户的权限分离。
 * Producer:消息生产者,就是投递消息的程序.
 * Consumer:消息消费者,就是接受消息的程序.
 * Channel:消息通道,在客户端的每个连接里,可建立多个channel.
 */
@Configuration
public class RabbitConfig {
    private final Logger logger = LoggerFactory.getLogger(this.getClass());

    @Value("${spring.rabbitmq.host}")
    private String host;

    @Value("${spring.rabbitmq.port}")
    private int port;

    @Value("${spring.rabbitmq.username}")
    private String username;

    @Value("${spring.rabbitmq.password}")
    private String password;

    //定义交换机
    public static final String EXCHANGE_A = "my-mq-exchange_A";
    public static final String EXCHANGE_B = "my-mq-exchange_B";
    public static final String EXCHANGE_C = "my-mq-exchange_C";

    //定义队列
    public static final String QUEUE_A = "QUEUE_A";
    public static final String QUEUE_B = "QUEUE_B";
    public static final String QUEUE_C = "QUEUE_C";

    //定义建立绑定的KEY值
    public static final String ROUTINGKEY_A = "spring-boot-routingKey_A";
    public static final String ROUTINGKEY_B = "spring-boot-routingKey_B";
    public static final String ROUTINGKEY_C = "spring-boot-routingKey_C";

    @Bean
    public ConnectionFactory connectionFactory() {
        CachingConnectionFactory connectionFactory = new CachingConnectionFactory(host, port);
        connectionFactory.setUsername(username);
        connectionFactory.setPassword(password);
        connectionFactory.setVirtualHost("/");
        connectionFactory.setPublisherConfirms(true);
        return connectionFactory;
    }

    @Bean
    @Scope(ConfigurableBeanFactory.SCOPE_PROTOTYPE)
    //必须是prototype类型
    public RabbitTemplate rabbitTemplate() {
        RabbitTemplate template = new RabbitTemplate(connectionFactory());
        return template;
    }

    /**
     * 第五步：把交换机，队列，通过路由关键字进行绑定，写在RabbitConfig类当中
     *
     *      * 针对消费者配置
     *      * 1. 设置交换机类型
     *      * 2. 将队列绑定到交换机
     *      FanoutExchange: 将消息分发到所有的绑定队列，无routingkey的概念
     *      HeadersExchange ：通过添加属性key-value匹配
     *      DirectExchange:按照routingkey分发到指定队列
     *      TopicExchange:多关键字匹配
     */

    @Bean
    public DirectExchange defaultExchange(){
        return new DirectExchange(EXCHANGE_A);
    }

    /**
     * 一个交换机可以绑定多个消息队列，也就是消息可以通过一个交换机把消息分发到不同的队列中去。
     * @return
     */
    @Bean
    public Binding bindingA(){
        return BindingBuilder.bind(queueA()).to(defaultExchange()).with(RabbitConfig.ROUTINGKEY_A);
    }

    @Bean
    public Binding bindingB(){
        return BindingBuilder.bind(queueB()).to(defaultExchange()).with(RabbitConfig.ROUTINGKEY_B);
    }

    /**
     * 获取队列A
     */
    @Bean
    public Queue queueA(){
        return new Queue(QUEUE_A,true);
    }

    /**
     * 获取队列B
     */
    @Bean
    public Queue queueB(){
        return new Queue(QUEUE_B,true);
    }

}
